Applied Mechanics and Materials Vols. 217-219

Abstract: Abstract. The feed water system is one of the most important system for nuclear power plant. Based on an analysis for the working principles of the AP1000 plant main feed water system, a novel fault Petri net model and fault diagnosis method are proposed. The main feed water flow low alarm is a serious fault for the feed water system, Petri net theory is adopted to establish the fault model for this fault signal. Through the consequence and account for this model, fault reasons and reasons probability for the main feed water flow low have been obtained. Application shows that, the fault Petri net has more advantages than the fault tree in qualitative analysis and quantitative calculation. And this method is a new route for the nuclear plant systems’ fault diagnosis.

Abstract: Automatic particle counter is widely used in particle size analysis, fluid particle pollution degree and filtering properties testing. In this article, the test-bed of Zhejiang Universe Filter Product Qulity Test Center used in fuel filtration efficiency test is introduced. According to the domestic and foreign relevant test standard, this test-bed adopts particle counting and multi-pass method for experimenting of international general approval. And by using the test-bed, we can manage to test and analyse filtration efficiency and dust holding capacity of automotive fule filter.

Abstract: A novel multiaperture connection method for three-dimensional shape measurement is presented. The principle of multiaperture method is to obtain subapertures relative location and orientation by measuring the object from different subapertures, and afterwards connecting them together. Rrotation and transformation of subapertures are the key problems to realize multiaperture connection. In order to improve calculability and efficiency of the connection algorithm, a new connection method using quaternion is proposed. The mathematic model of multiaperture connection associated with our proposed method is discussed, and the experimental measurement on the basis of digital grating projection system is carried out to demonstrate the validity of this suggested method. Compared with the conventional connection method, this method offers with such advantages as computational simplicity, high efficiency and reasonable accuracy.

Abstract: A new definition was proposed-bearing control; in the case the bearing subjects to both radial and axial force only, the deformation is roughly symmetry about the Y-axis. When axial preload is 0.4 times greater than radial force, the bearing is controllable. In the case the bearing is exposed to pure torque and axial load, and axial preload is 50 times of the torque, the bearing is controllable. When complex load is applied on the bearing and axial preload is more than 0.418F_r+0.46F_a, the bearing is controllable. The application of spring equivalent bearing to simplify the model; the analysis of the impact on bearing exerted by a variety of installation errors and determination of the best installation form; the relation between installation errors and bearing load, and the relation between axial preload and the best installation form under the condition that the bearing is controllable, all of those are mentioned.

Abstract: This paper discusses the changes of system lifetime and reliability functions in terms of the properties of Copulas when components are dependent, and provides a way in which you can judge the changes of systems with the definition of order according to the Copula of components.

Abstract: In wind turbine condition monitoring, the sensors often can not be installed to the ideal position. Compare the common signal processing method comprehensively and give the advantage of the fastICA algorithm in the wind turbine condition monitoring. Give the basic principle and mathematical model of the fastICA algorithm, while monitor and analysis the wind turbine state data based on the fastICA algorithm. The results show that this algorithm can separate the vibration characteristics of the tested compenent of the wind turbine from the vibration signals quickly and accurately.